Re: [eigen] Eigen::Matrix and cv::Mat conversions

[Benoit Jacob <jacob.benoit.1@xxxxxxxxx>]

2010/8/23 <lfrfly@xxxxxxxxxxx>

Eigen defaults to column-major.

Curious, is there a reason for this? When writing loops, most C and C++ programmers have ingrained the "columns as inner loop" philosophy for efficiency. Now, presumably Eigen matrices are not intended to be manually looped over too often, but it's still a curious choice.

All I can think of is that it's to simplify interactions with LAPACK implementations.

And with OpenGL too, and..... at the end of the day, we just have to pick a default :-)

Benoit
 

If you want row-major with Eigen you can do:
typedef Matrix<float,2,2,RowMajor> MyRowMajorMatrixType;

That's what I need, thanks.